1. Field of the Invention
The present invention concerns a folding station of a folding box gluing machine for processing a blank delivered along a conveying section with a controllable delivery speed, wherein the blank has a middle piece on which side pieces are attached at the sides of the middle piece, which are folded inward along folding grooves between the middle piece and the side pieces, across a folding line toward the lengthwise middle of the blank and then folded up in order to produce the folded boxes, with a folding strap that folds the side pieces upward, being guided by a folding shunt, a positioning roller, and one or more deflection and pressure rollers.
2. Description of the Related Art
A known folding box machine used to transform blanks into folded box tubes is disclosed in DE 102 41 448. The blanks correspond to a view of a ready-to-produce folding box. The folding must be performed with precision, since the folding will determine the angle trueness of the finished folded box.
In order to produce the folded box tube, folding straps or folding bands are used and arranged to lie against portions of the blank being folded up, or the side pieces of the folding box blank, and maintain the folding along the folding line. The folding straps are arranged so as to have a helical shape and are arranged to operate on the portions being folded. To effectively perform the folding operation, the folding straps travel at a speed corresponding to the speed of the blank. In order to ensure the angle trueness of the finished folded box, a plurality of loosely turning disks are arranged in the folding line, and make contact with the folding box blank in the vicinity of the folding lines.
Another known folding station for folding blanks is disclosed in DE 44 39 198 A1. Folding is performed using folding straps, which engage the side flaps of a blank from underneath. The folding straps thus travel from a plane underneath the blank to a plane above the middle piece of the blank. The axes of the folding straps are twisted relative to each other so that the surface of the folding strap facing the blank rotates by a total of about 180 degrees along the delivery path of the blank. In order to maintain close tolerances during the folding of the blanks, an edging device is arranged in the region of the folding lines of the blanks in the forward region of the delivery path.
It is evident from the described state of the art that exact folding along the folding lines and maintaining angle trueness of the blanks after folding present problems with the conventional folding process.